;; ---
;; 1.3

(define (proc a b c)
  (define (least a b c)
    (cond ((and (<= a b) (<= a c)) a)
          ((and (<= b a) (<= b c)) b)
          (else c))
    )
  (define (square a) (* a a))
  
  (- (+ (square a) (square b) (square c)) (square (least a b c)))
  )
